Data processing apparatus

ABSTRACT

A DATA PROCESSING SYSTEM HAVING A MAIN DATA PROCESSOR AND A PLURALITY OF REMOTE TERMINALS EACH HAVING DATA PROCESSING CAPABILITY. THE MAIN OR CENTRAL PROCESSOR IS COUPLED IN A POLLING ENVIRONMANT TO THE VARIOUS TERMINAL PROCESSORS VIA A COMMUNICATION LINK. COMMUNICATION OR DATA TRANSMISSION OF EACH OF THE VARIOUS PERIPHERAL OR TERMINAL PROCESSORS TO AND FROM THE CENTRAL DATA PROCESSOR IS CONTROLLED BY SEPARATE LINE DISCIPLINE PROCESSORS. A LINE DISCIPLINE PROCESSOR IS COUPLED AND RESPONSIVE TO THE RESPECTIVE DATA PROCESSOR AT EACH REMOTE SITE. THE LINE DISCIPLINE PROCESSOR AT EACH REMOTE TERMINAL EDITS AND ASSEMBLES THE INFORMATION TO BE TRANSMITTED AND IDENTIFIES, EDITS AND ASSEMBLES INFORMATION RECEIVED AND PERFORMS OTHER TASKS RELATED TO THE COMMUNICATION FUNCTION THEREBY PROVIDING MICRO-PROGRAMMED LINE DISCIPLING.

Feb. 16, 1971 c. c. PERKINS ETAL 3,564,509

DATA PROCESSING APPARATUS Filed April 22, 1968 18 Sheets-Sheet l CENTRALDATA PROCESSOR Ij GENERAL COMMUNICATION EXCHANGE I 1 7 J L MODEM MODEMMODEM I I I TERMINAL TERMINAL 3 23" TERMINAL COMPUTER COMPUTER COMPUTERNO. I N0. 2 Mom REMOTE LINE R X PROCESSOR DISCIPLINE PROCESSOR DATA COMMCONTROLLER TX ARITHMETIC FUNCTION UNIT GENERATOR 35 INVENTORS. comm/usc. PERKINS. ME MORY MEM JOHN H. PEDERSEN.

H0) r/Mc CHANG. 34 MICHAEL M. MALMER, JR.

A TTORNF Y Feb. 16, 1971 Filed April 22, 1968 C. C- PERKINS ETAL DATAPROCESSING APPARATUS 18 Sheets-Sheit S FIG.4.

MEMORY REMOTE ADDRESS PROCESSOR MATRIX MEMORY 7,3 I 4 5 LINE MEMORYDISCIPLINE ADDRESS AUX'UARY PROCESSOR MATRIX FD. MEMORY 4 M m DATA 00M.0 CONTROLLER FIG.8.

1971 c. c. PERKINS ETAL 3,564,509

DATA PROCESSING APPARATUS Filed April 22. 1968 18 Sheets-Sheet 4 FIG.5A.

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ES" 00 0| u no 0 E0 E2 E6 E4 E E3 E7 E5 FIG.5C. LEGEND.4BITMICROADDRESSSEARCH-E AND 1 an mono ADDRESS SEARCH-E4 j j a? LOAD uUPPER =(E4+E5)-TA2F LOAD u LOWER E2 CHARACTER ADDRESS SEARCH E3 UAC WORDADDRESS SEARCH a,

EXECUTE =5,

HEAD SW|TCHING=EO 0R E7 E0 2 61 ans DATA T0 mono E 2 61 ans mcnomom c.c. PERKINS ETAL 3,564,509

DATA PROCESSING APPARATUS Feb. 16, 1971 18 Sheets-Sheet 6 Filed April22, 1968 FIGJA- WA" ""1 -INITIALIZATION FOR START HALT Y0 Y4 0 Q Q Q i5352?. r l- DECO) R ncur WMT FOR Y? IYHRECI SET START an SAMPLE PULSEQLM DPF/*EFTF RESET R2 om TARF- CTO- f m TATE F Y5 Y2+Y6+Y YA ISAAAIAATE 39m YAF STROBE DCUF DATA mm HERE YI BBF SEARCH w PRESET(COMPDIPEFM)ENT FOR w l DPF A OOOI @0500 INCREENT YACF 0 011+ COUNT YACFP me A BBF- W-B BBF W mason Y3 E CTY'DBCY'DCCO CT?-DBCT-DCCO/ DECREMENTY awofw SET CHARACTER 0 VL FLAG COUNT was TmE ouT Y2 m A86 CHOOIOPCHTARF DCL'F DCLIF/ DCUF TIMIOUT Y6 SET R2 FLAG PCTI-TARF-DCLIFI1971 c. c. PERKINS ETAL 3,

DATA PROCES S ING APPARATUS Filed April 22, 1968 18 Sheets-Sheet 7 H678READY TO Y- TRIAIN%MIT x J VLFLAG-XMTCAR-BTGB SET BBF H5 UL3F-UYT Ysncounmz BT66 T0 IH i (new) SEARCH w m FOR w- RESET ||0| VL FLAGYACF-D-CT7+ YACF-P-CTZ Y9 ENABLE WNB+SFF Y RESETTINGBBF 1 mm FORSTARTBIT DBCO-BBF I on COMPLETE DBCYI'DCLIF-BBFH Y sT Agg snDBCU-DCLIFDBCO/ Y DECREMENT DBCY'DCL'F CHARACTER W Y coum DCUF'SFF DATABYY TIME Ham BEGINS STOP BIT n00 Y2F,Y|F V SET BBF 00 YO Y Y3 Y2DCLlF-YAF-SFF/ TRANSMIT Feb. 16, 1971 c. c. PERKINS ETAL 3,564,509

DATA PROCESSING APPARATUS Filed A rilzz, 1968 1a Sheets-Sheet 8 l6 5 MIN'6 msse/ I11 EIN ' 7 EHTI H 229 E MEMORY 4 HEAD SELECT E MATRIX M MEMORY0TH R INPUTS H 389 CPY FToB KIZXIE TRACK SELECTION IN EXCHANGE FIG.9A.

1971 c. c. PERKINS ETAL 3,

DATA PROCESSING APPARATUS Filed April 22, 1968 18 Sheets-Sheet 9 LOGICSYMBOL LEGEND. CE AND GATE ((5 OR GATE I if I97} I95 i gwc/ PECF B166E/PARITY we W ERRE/ PECF/ PETF PETF PARITY -2Q| F TIMING TO M m REGISTERS3. CPYBUU F 5 E comm GATING AND DECODER N SERIALIZER FOR EXCHANGE filmSTATE MACHINE juAc g 225 I I I him 2 ES4F ESZF m 5971,? 524 19 E 205EXCHANGE 5m MACHINE ADDRESS SEARCH EACF 1971 c. c. PERKINS ETAL3,564,509

DATA PROCESSING APPARATUS ["1 led Apli 1 DP, 1968 18 Sheets-Sheet l0 c.c. PERKINS ETAL 3,564,509

DATA PROCESSING APPARATUS Feb. 16, 1971 18 Sheets-Sheet 11 Filed April22, 1968 H 5 12552 :2 N2 5; :5 H A :2 my 1.1:. a: z? .5 .o 5 if A E AIILM32 AAIIAM am A H A to: lw A 5:58 o A r E 0% w 5 A 5% as: d L :22: a Aas 7 15 m ER A A A 5 :2 o mas: 4 0 A E2 :2 EN 535 M ww m 5:585 an m AM.J: n n1 r1 @5 m W E E 1 a E8: 22 A A: Ali! A 5 All] w A A 5 El 0225 352311A .523: -25 AT 5:223 E 3 =32 22 E E o; 0:; mvm 0 07.

Feb. 16, 1971 c. c. PERKINS ETAL 3,564,509

DATA PROCESSING APPARATUS l8 Sheets-Sheet 12 Filed April 22 1968 mozjswomom2 m OF mm ILQI O.

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Feb. 16, 1971 c. c. PERKINS ETAL 3,5

DATA PROCESSING APPARATUS Filed April 22, 1968 18 Sheets-Sheet 15 ul 2LL ll." 25 (9| L CONTROL MATRIX T0 REGISTERS I ,KI

18 Sheets-Sheet 14 C. C. PERKINS ETAL DATA PROCESSING APPARATUS mOm=2HNZMW NWHM 2 wok QMIWNR m "swa E512 E! w I u/ /../m m D :5 2T 52E THE :3H 23G: lwmmwfl @225; m2; 5 m 20$: 52032225222: a E .1; 23302222: a s x EESE: T m m a: w I: .21 52L 2 m E 53x23 Flaw g fi g 5 223:: i w h 2T; 5555022522 E: m 522: gm 1% m a 3 Sm A Feb. 16, 1971 Filed April 22,

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Feb. 16, 1971 c. c. PERKINS ETAL 3,564,509

DATA PROCESSING APPARATUS Filed Aaril 22, 1968 1a Sheets-Sheet 15RESTORE REGISTER EIHJII EIHIH X X X X N X 4 K N K N X CONTROLS OUTPUTINPUT 2 IMXII HDII'INXKNKKXN FUNCTION GENERATOR CONTROLS INPUT 1 AHHVOH[CARRY] POO dofifl"'" OOOOr-v-v-F Jlfln OOOOOOOOOOOOOO OOQO JzQI I Q O-v-Pv-Q-F- Jinn c3 0 ro o o o o o o o J'IQQDDDDDDDDO OPOF .aQnn D :2 :2D :a :1 :2 o o o o JQHH DDDDDDD -v-v-v-OO JLnIl DDDDDDD v-PPPdO'IflDDDDDDDD -v-Pv-P :Il'IH DDDDDDDOOOUOO r-r-v-r-v- O O O O Foo- O OO O v-v-v-u-v- O O O O O O O 1000 ACO1101O INSTRUCTION REGISTER STATECONTROLS AC1101OO ACO! ACOOOOO ACOOOO101O ACOOO1001 FIGJOA) MNEHONICFUNCTION CPYUI Feb. 16, 1971 c. c. PERKINS ETAL 3,564,509

DATA PROCESSING APPARATUS 1971 c. c. PERKINS ETAL 3,

DATA PROCESSING APPARATUS Filed April 22, 1968 18 Sheets-Sheet 17 POLL,ACKNOWLEDGEMENT, TRANSMISSION AND ACKNOWLEDGEMENT CENTRAL DATA POLL ACK.PROCESSOR ACK. c & MESSAGE K LINE DISCIPLINE S A A X S E B E PROCESSOR OD D M T T E X T T L O H l 2 X X C T POLL WITH NEGATIVE ACKNOWLEDGEMENTCENTRAL DATA POLL PROCESSOR LINE DISCIPLINE E PROCESSOR o T SELECTION,ACKNOWLEDGEMENT, MESSAGE RECEIPT AND ACKNOWLEDGEMENT CENTRAL DATA SELECTMESSAGE PROCESSOR E A A s E s A A x s E B o n n E N 0 n 0 M T T E x T 'Ic T 1 2 L Q A H 1 2 x x c A A LINE DISCIPLINE c c PROCESSOR x KSELECTION HITH NEGATIVE ACKNOWLEDGEMENT CENTRAL DATA sELEc'r PROCESSORLINE DISCIPLlNE PROCESSOR '1 x LEGEND FUNCTION MESSAGE FORMAT UnitedStates Patent 0 DATA PROCESSING APPARATUS Cornelius C. Perkins,Birmingham, John H. Pedersen, Detroit, Hoy Ying Chang, Westland, andMichael M. Malmer, Jr., Livonia, Mich., assignors to BurroughsCorporation, Detroit, Mich., a corporation of Michigan Filed Apr. 22,1968, Ser. No. 723,088

Int. Cl. G061 15/16, 15/40 US. Cl. 340-1725 19 Claims ABSTRACT OF THEDISCLOSURE A data processing system having a main data processor and aplurality of remote terminals each having data processing capability.The main or central processor is coupled in a polling environment to thevarious terminal processors via a communication link. Communication ordata transmission of each of the various peripheral or terminalprocessors to and from the central data processor is controlled byseparate line discipline processors. A line discipline processor iscoupled and responsive to the respective data processor at each remotesite. The line discipline processor at each remote terminal edits andassembles the information to be transmitted and identifies, edits andassembles information received and performs other tasks related to thecommunication function thereby providing micro-programmed linediscipline.

BRIEF DESCRIPTION This invention relates to a data processing system andmore particularly to an improved on-line, multi-terminal data processingsystem and a remote terminal therefore.

BACKGROUND It is well known that computers are being utilized at an everincreasing rate to perform various functions in the commercial,manufacturing and scientific world. The application of computers tovarious operations may conveniently be divided into two operating modes,namely: on-line systems and batch processing systems. A real-time oron-line system may be defined as a data processing system in which thetime delay in a central processor responding to an input stimulus isnegligible in the time reference of the users equipment.

In a typical on-line commercial computer application it is often desiredto access and process a centrally located data file. For example in abank it is often necessary to obtain or update certain account balanceskept in a file of bank accounts. Similarly insurance companies find itis necessary to periodically update information in various files such asthe amount of insurance, the premium data and the extent of insurancecoverage for each insured person. High speed electronic data processingsystems are commonly used for storing files of information for banks,insurance companies and the like. Further, in such businesses, it isoften desirable to have a centrally located data processing systemincluding high speed electronic central processor and peripheralequipment and to employ remote terminal devices for entering informationfrom any of a number of remote terminals. Such remote terminals may belocated, for example, at branch offices of the banks or insurancecompanies.

Prior art systems of which applicants are aware employed conventionalteletype writer terminals as the remote terminals for transmittingmessages in the form of alphanumeric pulse coded signals to the centralcomputer and for receiving replies therefrom. Such a system of necessitywas designed to meet a number of requirements including means forassuring that messages transmitted from and received by the dataprocessor are received free from error. Also since the central dataprocessor typically operates at speeds much faster than a teletypewriterterminal, the system should be arranged to permit the processor to worksubstantially independent of any terminal while the operator ispreparing and transmitting the message. In addition, the system shouldpermit entry of a message from any typewriter without interfering withthe operation of the other similar terminals. In the past the systemcontrol has been defined by the central data processor. This representeda considerable Work load on the central processor in that the messageformating and system control consumed a considerable portion of thecentral processors time.

In commercial banking and other on-line systems it is desirable to havethe ability to perform data processing at the remote stations. Prior artsystems which use the teletypewritertype remote data terminal generallyrequired a batch type operation for transmitting data from the remotelyoperated computer via the teletypewriter terminal to the main processor.As hereinabove stated this type operation imposed the transmissioncontrol function on the main processor which had to format and assembleall messages and exercise system priority control. Thus the overallefficiency or throughput of the central data processor was greatlydecreased because of its time consuming system function control tasks.

Accordingly, it is an object of the present invention to improve theefficiency of transmission of data between a plurality of remotelysituated computers and a central data processor.

It is a further object of the present invention to increase theoperating efficiency of a plurality of remotely situated data processorswhich are on-line with a central data processor.

It is a further object of the present invention to relieve the centraldata processor in an on-line data processing system environment from thesupervisory control of all information transmitted to remotelycontrolled data processors.

It is yet another object of the present invention to increase theoif-line computing capability of a plurality of data processors whichare connectable on-line with a central data processing system.

It is a still further object of the present invention to I improvecommunications between a central data processor and the plurality ofremotely situated data processors.

It is yet another object of the present invention to provide improvedmeans for controlling the communication on-line between a central dataprocessor and a plurality of remotely situated processors arranged in apolling environment.

BRIEF STATEMENT OF THE INVENTION The above objects and other desirableaspects are achieved in accordance with applicants invention byutilizing a line discipline processor at each remote terminal forcontrolling transmission line discipline between the remote processorand a central processor linked in an online, real time system. Thissystem architecture relieves both the remote processor and the centralprocessor from various tasks including messages assembly, messageformating, message editing and parity checking which are associated withon-line, real time data transmission systcms. The line disciplineprocessor in accordance with a licants invention communicates with itsremote rocessor by setting appropriate stages of a flag register in theline discipline processor which are periodically monitored by the remoteprocessor. The remote processor thereby controls the access to and fromthe line discipline processor. After the remote processor has assembleda message to be transmitted, it signals the line processor that it isready to transmit a message. When appropriate,

as indicated by the flag register in the line processor, the message istransferred to the transmit buffer or tank of the line disciplineprocessor. Thereafter the remote processor is free to return to itsnormal program and process other data while the line disciplineprocessor awaits a poll inquiry signalling its opportunity tocommunicate with the central processor. Similarly in the receive mode,the line discipline processor responds to a selection inquiry of thecentral processor and assembles, edits and parity checks the messagereceived from the central processor for the remote processor. After theline discipline processor determines that a message has been properlyreceived and assembled, it sets appropriate flags to indicate to theremote processor that it has a complete message for it from the centralprocessor. The remote processor then interrupts its program momentarilyto receive and execute the task involving the data transmitted to itfrom the central file, thereafter returning to its normal program.

For a more complete understanding of applicants in vention as to itspreferred structure and method of operation reference may be had to thefollowing detailed description in conjunction with the drawings wherein:

FIG. 1 is a block diagram of a data processing system incorporating theprinciples of the present invention.

FIG. 2 is a symbolic block diagram of a remote ter minal computer inaccordance with one aspect of the principles of the present invention.

FIG. 3 is a simplified functional block diagram of a remote computerterminal embodying the principles of the present invention.

FIG. 4 is a simplified block diagram illustrating the remote processorand line discipline processor of applicants terminal computer and theirrespective relationship for accessing the main and auxiliary memoryassociated therewith.

FIGS. 5A, 5B and 5C together illustrate the structural and logicaloperation of the state machine of applicants line discipline processor.

FIGS. 6A, 6B and 6C together illustrate the structure and logicaloperation of the line discipline processor state machine forinter-processor information exchange.

FIGS. 7A, 7B and 7C together illustrate the structure and logical fiowdiagrams for the datacomm controller state machine in the transmit andreceive mode respectively.

FIG. 8 is a layout diagram showing the positional orientation of FIGS.9A through 90.

FIGS. 9A through 9G together comprise a detailed logical block diagramof the remote terminal in accordance with the principles of the presentinvention.

FIGS. 10A and 10B comprise a typical listing and description of arepertoire of instructions available for use in a terminal computerembodying the principles of the present invention.

FIGS. 11A through 11D illustrate the format of typical message exchangesbetween a remote terminal and a central data processor.

FIG. 12. illustrates the function and operation of the various stages ofthe flag register of applicants line discipline processor.

Referring now to FIG. 1 there is shown a block diagram of a typicalsystem embodying the principles of the present invention. As shown acentral data processor 11, for example comprising a Burroughs B5000 andits associated complement of input/output storage devices 13, 15, 17 and19, is connected via a communication link 21 to a plurality of remoteterminal computers 23. ln a typical installation, the central dataprocessor 11 would be located in the main business ofiice of acommercial firm, for example a bank, and the remote terminals would belocated in branch offices of the commercial firm. The branch offices maybe in the same general location or remote therefrom and in each casethey are connected via a modem 25 to a communication link. The link 21for example, may comprise telephone lines connecting the terminals 23via a central communication exchange 27 to the site of central processor11. In the preferred embodiment of applicants invention the remoteterminal computers are arranged in a polling and selection environmentwhereby the respective terminal computers 23 are arranged to performdata processing functions in accordance with its respective programolT-line and to communicate with the central data processor whenever thecentral data processor addresses the terminal and indicates that it isready to initiate data communication with the addressed terminal.

Referring now to FIG. 2 there is illustrated a simplified block diagramof a terminal computer 23 in accordance with the principles of thepresent invention. For purposes of illustration applicants terminalcomputer may be described as comprising three sections: a remoteprocessor 33 including a memory 34, an arithmetic unit 35, an inputkeyboard 37 and an output printer 39; a line discipline processor 41with its function generator 43 and memory 45; and a datacomm terminalcontroller 47. The structure and operational inter-relationship of thesections of the terminal computer 23 will be discussed in detailhereinafter in conjunction with FIGS. 3 and 9, with similar referencenumerals being used to designate the respective sections of the terminalcomputer 23.

Briefly the remote or terminal processor 33 comprises a stored programmachine in which object data is manipulated in an arithmetic unit 35 inaccordance with a sequence of micro program instructions stored in andwithdrawn from the main memory in a predetermined sequence. Keyboard 37is arranged to enter program and object data into the processor and theoutput device 39 is arranged to generate a hard copy printout. Theremote processor 33 communicates in an on-line mode with a central dataprocessor 11 via the line discipline processor 41 and the datacontroller 47. The datacomm controller 47 is in essence a buffer forreceiving and transmitting information in a serial bit form under thecontrol of the line discipline processor. The line discipline processor41 is a stored program machine in which the stored micro programcontrols the assembly, editing and formating of messages to betransmitted to and which are received from the central data processor 11for the remote processor 33.

In response to a polling inquiry from the central processor, the linediscipline processor responds in accordance with its activity state asdetermined by the processor 33. As will hereinafter be more fullyexplained, messages prepared by the processor 33 are transmitted to thememory 45 and upon appropriate signal from the cen tral processor 11 aretransferred under the control of the line processor 41 to the datacontroller 47 to await transmission via the transmission link to thecentral processor 11. After the message has been transferred to the linediscipline processor 41, the remote processor 33 is free to return andperform other tasks while processor 41 awaits transmission to andresponse from the central processor 11. The line discipline processor 41performs parity checks on transmitted and received data and mayautocatically establish and insert appropriate message headers. Inresponse to a selection inquiry from the central processor 11 the linediscipline processor transmits a message to inform the central processorwhether it is ready to receive a message. Whenever a message has beenreceived and verified and stored in the memory 45 of the line disciplineprocessor 41, the line discipline processor sets appropriate flagregisters (FIG. 12) to signal the main processor that it has a messagefor it. The processor 33 periodically monitors the state of the flagregister and appropriately interrupts its processing program to receivethe data and execute the command intermediate the successive steps ofits process program being run.

Referring now to FIG. 3 there is shown a block diagram of the terminalcomputer 23 embodying the principles

